Malware Analysis Report

2024-12-07 20:18

Sample ID 241117-md8y8sxjg1
Target skuld.exe
SHA256 8e3601302c0294914808b6537cd27de961d087ba0807590b981b7f8c8aa5eee6
Tags
skuld persistence
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral2

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

8e3601302c0294914808b6537cd27de961d087ba0807590b981b7f8c8aa5eee6

Threat Level: Known bad

The file skuld.exe was found to be: Known bad.

Malicious Activity Summary

skuld persistence

Skuld family

Adds Run key to start application

Unsigned PE

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

Views/modifies file attributes

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-11-17 10:22

Signatures

Skuld family

skuld

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2024-11-17 10:22

Reported

2024-11-17 10:25

Platform

win7-20240903-en

Max time kernel

118s

Max time network

120s

Command Line

"C:\Users\Admin\AppData\Local\Temp\skuld.exe"

Signatures

N/A

Processes

C:\Users\Admin\AppData\Local\Temp\skuld.exe

"C:\Users\Admin\AppData\Local\Temp\skuld.exe"

Network

N/A

Files

N/A

Analysis: behavioral2

Detonation Overview

Submitted

2024-11-17 10:22

Reported

2024-11-17 10:25

Platform

win10v2004-20241007-en

Max time kernel

147s

Max time network

153s

Command Line

"C:\Users\Admin\AppData\Local\Temp\skuld.exe"

Signatures

Adds Run key to start application

persistence
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-3442511616-637977696-3186306149-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Realtek HD Audio Universal Service = "C:\\Users\\Admin\\AppData\\Roaming\\Microsoft\\Protect\\SecurityHealthSystray.exe" C:\Users\Admin\AppData\Local\Temp\skuld.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\skuld.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 4516 wrote to memory of 3944 N/A C:\Users\Admin\AppData\Local\Temp\skuld.exe C:\Windows\system32\attrib.exe
PID 4516 wrote to memory of 3944 N/A C:\Users\Admin\AppData\Local\Temp\skuld.exe C:\Windows\system32\attrib.exe

Views/modifies file attributes

evasion
Description Indicator Process Target
N/A N/A C:\Windows\system32\attrib.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\skuld.exe

"C:\Users\Admin\AppData\Local\Temp\skuld.exe"

C:\Windows\system32\attrib.exe

attrib +h +s C:\Users\Admin\AppData\Local\Temp\skuld.exe

Network

Country Destination Domain Proto
US 8.8.8.8:53 104.219.191.52.in-addr.arpa udp
US 8.8.8.8:53 172.214.232.199.in-addr.arpa udp
US 8.8.8.8:53 4.159.190.20.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 28.118.140.52.in-addr.arpa udp
US 8.8.8.8:53 200.163.202.172.in-addr.arpa udp
US 8.8.8.8:53 206.23.85.13.in-addr.arpa udp
US 8.8.8.8:53 217.135.221.88.in-addr.arpa udp
US 8.8.8.8:53 19.229.111.52.in-addr.arpa udp

Files

N/A